Control valve



Nov. 29, 1966 Original Filed Sept. 10, 1964 R. c. BUELER 3,288,539

CONTROL VALVE 2 Sheets-Sheet l 4 36 J l Q 14 19 30 33 RES. 3 20 8 COMPRES.

INVENTOR FIG. RICHARD c. BUELER Nov. 29, 1966 R. c. BUELER 3,288,539

CONTROL VALVE Original Filed Sept. 10, 1964 2 Sheets-Sheet 2 FIG. 4

FIG. 3

(n cu INVENTOR RICHARD Cl BUELER United States Patent r 3,288,539CONTROL VALVE Richard C. Bueler, Glendale, Mo.,assignor to WagnerElectric Corporation, St. Louis, Mo., a corporation of DelawareContinuation of application Ser. No. 395,433, Sept. 10, 1964. Thisapplication Mar. 28, 1966, Ser. No. 538,104 21 Claims. (Cl. 303-43) Thisapplication is a continuation of application Serial No. 395,433, filedSeptember 10, 1964, and now abandoned.

This invention relates to fluid pressure systems and in particular tocontrol valves therefor having emergency means therein for automaticallyactuating said systems.

In past fluid'pressure systems, particularly those related to vehiclebraking, various emergency control devices have been employed to effectemergency braking of the vehicle in the event of malfunction of saidsystems eflecting loss of fluid pressure therein, and the usualemergency control means were incorporated in said fluid pressure systemsin the form of separate independent valves, such as the well-knownemergency valve or the relay-emergency valve. One of the undesirablefeatures of the past systems was that a separate valve was compatiblyemployed in said systems along with the other necessary valving thereinto effect the emergency function, and, of course, it is apparent thatsuch separate valving manifestly increased the initial cost of saidsystems as well as the maintenance or cost of upkeep therefor. Anotherundesirable or disadvantageous feature of the use of a separateemergency valve in a fluid pressure system was particularly evident inthe past tractor-trailer braking systems wherein the emergency valvewhen actuated due to low pressure in said system effected energizationof only the trailer brakes; however, it would have been more desirableto have also eifected energization of the tractor brakes in order toobtain maximum braking effort for such tractor-trailer braking systemsunder such low pressure or emergency conditions. In conjunction with theaforementioned undesirable feature of the past tractor-trailer brakingsystems, another undesirable feature was the inability of the operatorto actuate the tractor brakes in the event the treadle or treadlelinkage to the system application valve was lost, disengaged, broken, orfor some other reason became inoperable to effect actuation of saidapplication valve. Still another undesirable or disadvantageous featurein the past tractor-trailer fluid pressure systems utilizing a separateemergency valve was that premature tractor movement was not obviateduntil suflicient operating pressure was attained in the system pressurereservoir, such as encountered in moving a tractor which had been parkedfor a period of time.

The object of the present invention is to provide a novel fluid pressuresystem and novel control valve means therefor which obviates theaforementioned undesirable or disadvantageous features, and this andother objects and advantageous features of the present invention willbecome apparent hereinafter.

Briefly, the invention embodies a fluid pressure system having a pair offluid pressure sources and a fluid pressure responsive motor and alsocontrol means for normally effecting the application of fluid pressurefrom one of said sources to said motor including means responsive tofluid pressure in the other of said sources less than a predeterminedamount to also effect the application of fluid pressure from said onesource to said motor.

In the drawing which illustrates embodiments of the invention,

FIG. 1 is a diagrammatic view of a fluid pressure system having controlvalve means therein embodying the present invention,

FIG. 2 is a greatly enlarged cross-sectional view of the control valvemeans of FIG. 1,

FIG. 3 is a cross-sectional view of another control valve meansembodying the present invention for use in the fluid pressure system ofFIG. 1, and

FIG. 4 is another cross-sectional view of valve control means embodyingthe present invention for use in the fluid pressure system of FIG. 1.

Referring now to the drawings in detail and in particular to FIG. 1, afluid pressure system 1 is shown having fluid pressure generating meansor compressor 2 connected with the inlet port of a control orapplication valve 3 by a conduit 4 having a reservoir 5 interposedtherein, and a check valve 6is provided in said conduit to provideuni-directional pressure fluid flow from said compressor to saidreservoir. Another conduit 7 is connected between the outlet port of thecontrol valve 3 and a fluid pressure responsive motor of brake chamber 8which is operatively connected with linkage means, such as slackadjustor 9, for controlling the energization of a friction device (notshown). Another conduit 10 has one end connected with the emergency orcontrol port of the control valve 3 and the other end thereofintersecting with the conduit 4 between the compressor 2 and check valve6, and another reservoir 11 is interposed in the conduit 10. To completethe description of the system 1, a push-pull hand valve 12 of the typewell known in the art is interposed in the conduit 10 between thereservoir 11 and the control valve 3, said push-pull valve 12 beingmanually operable between a venting position which interrupts pressurefluid communication between the reservoir 11 and the emergency port 21of said control valve and exhausts said emergency port to the atmosphereand a charging position'connecting saidemergency port in pressure fluidcommuni cation with the reservoir 11.

The control valve 3, FIG. 2, is provided with a housing 13 having a bore14 therein, which forms an inlet chamber, and a counterbore 15 in axialalignment with said bore. A radially extending wall 16 is integrallyformed with the housing 13 between the bore 14 and counterbore 15, and aconnecting passage 17 extends through said wall between said bore andcounterbore, said wall having a valve seat 18 thereon in circumscribingrelation with said connecting passage. Inlet and outlet ports 19 and 20which respectively receive conduits 4 and 7, as previously mentioned,are provided in the housing 13 connecting with the bore 14 andcounterbore 15, respectively, and a control or emergency port 21 whichreceives the conduit 10, as previously mentioned, is also provided insaid housing connecting with the counterbore 15 adjacent the midportionthereof. A plurality of mounting flanges 22 are provided adjacent to theupper end of the housing 13 and are fixedly connected by suitable means,such as studs 23, with like mounting flanges 24 provided on a closuremember 25 for the upper end of the counterbore 15, said closure memberhaving a guide opening 26 therethrough to receive the force transmittinglinkage of an operator controlled lever (not shown).

A valve guide member 27 is positioned in the bore 14 againstdisplacement by a snap ring and groove assembly 28 provided adjacent tothe lower end of said bore, said lower end of said bore forming anexhaust port 29. The

valve guide member 27 is provided with an axial valve bore 30 in which avalve element 31 is slidably received, and seals 32, 33 are carried insaid valve guide member in sealing engagement with said valve elementand the housing bore 14, respectively. The valve element 31 is providedwith an axial exhaust passage 34 therethrough, and an annular resilientseal or disc 35 is provided on the upper end of said valve element incircumscribing relation with said exhaust passage. A valve spring 36biased between the valve guide member 27'and the valve element 31normally urges the valve element seal 35 into sealing engagement withthe valve seat 18 provided on the housing Wall 16 to normally interruptpressure fluid communication through the connecting passage 17 betweenthe inlet and outlet ports 19, 20 while'establishing pressure fluidcommunication between said outlet port and the exhaust port 29 throughsaid connecting passage and the valve element exhaust opening 34. 7

An application member or reaction piston 37' is slidably received in thecounterbore 15 defining therein with the housing wall 16 an outletchamber 38 connected in open pressure fluid communicationwiththe outletport 20 at all times, and a return spring 39 is positioned in saidoutlet chamber between said reaction piston and said housing wallnormally urging the upper end of said reaction piston toward abuttingengagement with the counterbore closure member 25. Spaced seals 40, 41are provided in the peripheralportionof the reaction piston 37 insealing engagement with the counterbore 15, and a peripheral groove 42is also provided in said reaction piston between said seals in openpressure fluid communication with the emergency port 21 at all times.The reaction piston 37 is also provided with stepped bores 43, 44therethrough, and a seal 45 is disposed in said stepped bore 44. Snapring and groove assemblies 46, 47 are respectively provided adjacent themid-portion and upper end of the stepped bore 43, and a pre-compressedmetering spring and retainer assembly 48 is slidably contained withinsaid stepped bore in abutting engagement with the snap rings 46, 47. Anemergency or control piston 49 is slidably received in the stepped bore43 having a peripheral seal 50 in sealing engagement with said steppedbore, and said emergency piston is provided with an integral extension51 slidably received in the stepped bore 44 in sealing engagement withthe seal 45 and having a lower or free end extending into the outletchamber 38. An expansible control or emergency chamber '52 is defined inthe stepped bore 43 by the emergency piston and extension 49 and 51, anda passage :53 in the reaction piston37 connects said emergency chamberin open pressure fluid communication with the reaction piston peripheralgroove 42 at all times. A valve seat 54 is provided on the lower ortfreeend of the emergency piston extension 51 for engagement with the valveelement 3.1, and an auxiliary exhaust passage 55 extends coaxiallythrough said valve seat and said extension. To complete the descriptionof the control valve 3, an emergency spring 56 has one engaged with theupper end of the emergency piston 49 and the other end thereof engagedwith a thimble or cup-shaped retainer 57 to urge said retainer intodisplacement preventing engagement with the snap ring 46.

Under normal operating conditions with the hand valve 12 in the chargingposition thereof to effect open pressure fluid communication between thereservoir 1-1aud the emergency port 21 of the control valve 3, fluidpressure generated by the compressor 2 flows through the conduits 4 and10, the reservoir '11, and the push-pull valve 12 into the emergencyport 21 of the control valve 3 and therefrom through the peripheralgroove 42 and passage 53 of the reaction piston 37 into the emergencychamber 52. The fluid pressure so established in the emergency chamber'52 acts on the effective area of the emergency piston 49 therein toestablish an emergency force acting against the compressive force of theemergency spring 56 to move said emergency piston upwardly in thereaction piston counterbore '43 to its inoperative position in abuttingengagement with the spring'retainer 57 and snap ring 46. The fluidpressure generated by the compressor 2 also flows through the conduit 4,the uni-directional valve *6 and the reservoir 5 into the inlet port 19of the control valve 3 and therefrom to the-inlet chamber 14. From the[foregoing it .is apparent that the reservoir 5 is a protected reservoirsince the uni-directional valve 6 protects said reservoir against lossof fluid pressure therefrom due to a malfunctioning compressor and/ orleaks in the system 1 ahead of the reservoir 5. With the fluid pressureso established in the reservoirs 5, .11 and the emergency chamber 5-2 ofthe control valve 3, the component parts of the control valve are now-positioned as shown in the drawings.

If the operator desires to elfect a braking application, amanually-applied force on the metering spring and retainer assembly 48moves the reaction piston 37 downward-1y against the compressive forceof the return spring 39 to engage the valve seat 54 on the emergencypiston extension 5 1 with the valve element 31 to close the valveelement exhaust opening 34 and the emergency piston exhaust passage 55and interrupt pressure fluid communication between the outlet andexhaust ports 20 and 29. Further downward movement of the reactionpiston 37 serves to disengage the valve element 31 trom the valve seat)18 on the housing wall 16 to open the connecting passage 17 andestablish pressure fluid communication between the inlet and outletports 19 and 20. In this manner, pressure fluid flows from the reservoir5 through the conduit 4, the inlet port and chamber 19 and 14, theconnecting passage 17, the outlet chamber and port 38 and 20, andthrough the conduit 7 to actuate the brake chamber 8 which, in turn,rotates the slack adjuster 9 to energize the wheel brake assemblyassociated therewith (not shown).

When the reaction force of the fluid pressure in the outlet chamber-38acting on the effective area of the reaction piston 37 therein issubstantially equal to the applied force, said reaction piston is movedupwardly against the compressive force of the metering spring andretainer assembly 48 wherein the valve element 31 is positioned inlapped engagement with the valve seat 18, and the valve seat 54 on theemergency piston extension 51 is positioned in lapped engagement withsaid valve element. If greater braking eifort is desired, the manuallyapplied force is increased, and the component parts of the control valve3 function in the same manner as previously described to again move saidcomponent parts to their lapped positions.

When the desired braking effort is attained, the manually applied forceis removed from the reaction piston 37 wherein the compressive force ofthe return spring 39 and the reactive force on said reaction pistonserve to move said reaction piston upwardly toward its original orinoperative position, and the valve spring 36 returns the valve element31 into sealing engagement with the valve seat 18. Initially, thisupward movement sealably re-engages the valve element 31 with the valveseat 18 to again interrupt pressure fluid communication between theinlet and outlet ports 19 and 20, and further upward movement of thereaction piston 37 disengages the valve seat 54 on the emergency pistonextension 51 from said valve element to re-establish pressure fluidcommunication between the outlet port and exhaust ports 20 and 29 toeifect de-energization of the wheel brake assembly associated therewithby exhausting the established fluid pressure to the atmosphere from thebrake chamber 8 through the conduit 7, the outlet port and chamber 20and 38, the connecting passage 17, the valve element exhaust passage 34,and the exhaust port 29.

Under emergency conditions when the fluid pressure in the reservoir 11is reduced or lost due to a malfunctioning compressor and/or leaks inthesystem 1 or the like, the fluid pressure in the emergency chamber52 iscorrespondingly reduced along with the emergency force on the emergencypiston 49. When the fluid pressure in the emergency chamber 52 is soreduced to a predetermined minimum value, the compressive force of theemergency spring 56 overcomes the opposing, reduced emergency force andserves to move the emergency piston 49 downwardly in the reaction pistonbore 43 relative to the reaction piston 37 to engage the valve seat 54on the emergency piston extension 51 with the valve element 31 to effectautomatic actuation of said valve element under emergency conditions.This emergency actuation of the valve element 31 by the emergency piston49 initially interrupts pressure fluid communication between the outletand exhaust ports 20 and 29 and thereafter establishes pressure fluidcommunication between the inlet and outlet ports 19 and 20, as describedhereinbefore, to effect emergency energization of the wheel brakeassembly (not shown).

In the event that the operator treadle or treadle linkage (not shown) islost, broken, disengaged from the control valve 3, or for some otherreason becomes inoperable for transmitting the applied force to thereaction piston 37, the operator can manually actuate the system 1 toeffect or simulate emergency conditions by manually moving the push-pullvalve 12 to the venting position thereof to interrupt pressure fluidcommunication between the reservoir 11 and the emergency port 21 of thecontrol valve 3 and exhaust said emergency port to the atmosphere. Whenthe system 1 is manually actuated in this manner to effect an emergencycondition, fluid pressure in the emergency chamber 52 is vented to theatmosphere through the reaction piston passage 53, the peripheral groove42, the emergency port 21 and the conduit to the push-pull valve 12.Exhaustion of the fluid pressure from the emergency chamber 52eliminates the emergency force on the emergency piston 49, therebypermitting the opposing compressive force of the emergency spring 56 tomove said emergency piston relative to the reaction piston 37 and effectautomatic actuation of the valve element 31, as described hereinbefore,along with the resulting energization of the wheel brake assembly (notshown).

Referring now to FIG. 3, a control valve 101 is shown havingsubstantially the same component parts and functioning in the system 1in substantially the same manner as the previously described controlvalve 3 with the following exceptions.

The control valve 101 is provided with an extension 102 on the reactionpiston 37 having a valve seat 103 on the lower or free end thereof forengagement with the valve element 31, and the stepped bore 44 of saidreaction piston extends coaxially through the reaction piston extension102 and valve seat 103. The emergency piston extension 51 is slidablyreceived in the stepped bore 44 in sealing engagement with the seal 45,and the valve seat 54 on the free end thereof is adapted for engagementwith the valve element 31 only under emergency conditions.

Under normal operating conditions with the push-pull valve 12 in thecharging position thereof to effect pressure fluid communication betweenthe reservoir 11 and the emergency chamber 52 of the control valve 101,the component parts of the control valve 101 are positioned as shown inthe drawing. An applied force on the reaction piston 37 moves saidreaction piston downwardly to engage the valve seat 103 of the reactionpiston extension 102 with the valve element 31 to effect actuation ofsaid valve element and the resulting energization and de-energization ofthe wheel brake assembly (not shown), as previously describedhereinbefore.

Under emergency conditions when the fluid pressure in the reservoir 11is reduced or lost due to a malfunctioning compressor and/ or leaks inthe system 1 or the like, the fluid pressure in the emergency chamber 52is correspondingly reduced, which effects a reduction of the emergencyforce on the emergency piston 49. When the fluid pressure in theemergency chamber 52 is so reduced to a predetermined minimum value, thecompressive force of the emergency spring 56 overcomes the opposing,reduced emergency force and serves to move the emergency piston 49downwardly in the reaction piston bore 43 relative to the reactionpiston 37 to engage the valve seat 54 on the emergency piston extension51 with the valve element 31 to effect automatic actuation of said valveelement under emergency conditions, as previously describedhereinbefore. Of course, when the system 1 is manually actuated toeffect an emergency condition, the emergency piston 49 functions in thesame manner to effect automatic actuation of the valve element 31.

Referring now to FIG. 4, a control valve'201 is shown havingsubstantially the same component parts and functioning in the system 1insubstantially the same manner as the previously described controlvalves 3 and 101 with the following exceptions.

The control valve 201 is provided with stepped extensions 202, 203 onthe emergency piston 49 having a valve seat 204 on the lower or free endof the stepped extension 203. The emergency piston extension 202 isslidable in the reaction piston bore 44 in sealing engagement with theseal 45, and the auxiliary exhaust passage 51 extends coaxially throughthe stepped extensions 202, 203 and the valve seat. A shoulder 205 isdefined between the stepped extensions 202, 203 having an effective arearesponsive to fluid pressure in the outlet chamber 38, and the effectivearea of the shoulder 205 is in a predetermined ratio with the effectivearea of the shoulder 206 on the emergency piston 49 which is responsiveto the fluid pressure in the emergency chamber 52.

Under normal operating conditions with the push-pull valve 12 in thecharging position thereof to effect pressure fluid communication betweenthe reservoir 11 andthe emergency chamber 52 of the control valve 201,the component parts of the control valve 201 are positioned as shown inthe drawing. An applied force on the reaction piston 37 moves saidreaction piston downwardly to engage the valve seat 204 on the emergencypiston extension 203 with the valve element 31 to effect actuation ofsaid valve element and the resulting energization and de-energization ofthe wheel brake assembly (not shown), as previously describedhereinabove.

Under emergency conditions when the fluid pressure in the reservoir 11is reduced or lost due to a malfunctioning compressor and/or leaks inthe system 1 or the like, the fluid pressure in the emergency chamber 52is correspondingly reduced, and since the emergency force on theemergency piston 49 in opposition to the emergency spring 56 is createdby the fluid pressure in said emergency chamber acting on the effectivearea of the shoulder 206, said emergency force is also correspondinglyreduced. When the fluid pressure in the emergency chamber 52 is soreduced to a predetermined minimum value, the compressive force of theemergency spring 56 overcomes the opposing reduced emergency force andserves to move the emergency piston 49 downwardly in the reaction pistonbore 43 relative to the'reaction piston 37 to engage the valve seat 204of the emergency piston extension 203 with the valve element 31 toeffect automatic actuation of said valve element under emergencyconditions to interrupt pressure fluid communication between the outletand exhaust ports 20 and 29 and establish pressure fluid communicationbetween the inlet and outlet ports 19 and 20, as previously describedhereinabove. The fluid pressure so established in the outlet chamber 38acts on the effective area of the shoulder 205 creating a reaction forcewhich is additive to the emergency force in opposition to thecompressive force of the emergency spring 56; therefore, theestablishment of the reaction force serves to effect a meteredapplication of fluid pressure from the inlet port 19 to the outlet port20. In other words, when the output fluid pressure acting on theshoulder 205 attains a magnitude great enough to compensate for the lossof fluid pressure in the emergency chamber, the emergency piston 49 ismoved upwardly against the emergency spring 56 to effect lappedengagement between the valve element 31 and the housing valve seat 18and between said valve element and the valve seat 204. Further loss offluid pressure from the system 1 and the emergency chamber will,ofcourse, eifect further metering of pressure fluid from the inlet port19 to the outlet port 20 to increase the magnitude of the ouput fluidpressure acting on the effective area of shoulder 205 to compensate forsaid further pressure fluid loss and return the component parts of thecontrol valve 201 to their lapped positions, as described above, underemergency conditions. The metering application of the control valve 201under emergency conditions provides for smoother or less abruptenergization of the wheel brake assembly (not shown) under emergencyconditions. Further, if the system 1 is manually actuated by theoperator to effect an emergency condition, the component parts of thecontrol valve 201 will function in the same manner, as described above,to effect a metered application of fluid pressure from the inlet port 19to the outlet port 20.

From the foregoing it is now apparent that a novel system and novelcontrol valves meeting the objects and advantages set out hereinbeforeare provided and that changes or modifications to the preciseconfigurations, shapes or details of the constructions set forth in thedisclosure by way of illustration may be made by those skilled in theart without departing from the spirit of the invention as defined by theclaims which follow.

The embodiments of the invention in which an exclusive property orprivilege is claimed are defined as follows:

1. A control valve comprising a housing, application means movable insaid housing and defining with said housing a pressure fluid flowpassage therethrough, said application means being movable in responseto an applied force toward a position in said flow passage establishingpressure fluid flow therethrough, said application means including anexpansible fluid pressure chamber, and resiliently urged means opposingfluid pressure expansion of said chamber, said resiliently urged meansbeing automatically movable toward a position in said flow passage toestablish pressure fluid flow therethrough in response to fluid pressurein said chamber less than a predetermined value.

2. The control valve according to claim 1, comprising a reaction area onsaid resiliently urged means responsive to the established fluidpressure in said flow passage to oppose the automatic movement of saidresiliently urged means.

3. The control valve according to claim 1, comprising a pair of additiveareas on said resiliently urged means and in said chamber and flowpassage, respectively, the established fluid pressure in said flowpassage acting on the area therein to establish a force opposing theautomatic movement of said resiliently urged means to compensate for thereduction of the additive force of the fluid pressure in said chamberacting on the area therein when the fluid pressure in said chamber isless than the predetermined value.

4. The control valve according to claim 1, wherein said applicationmeans also includes a member movable in said housing, said resilientlyurged means including another member adapted for relative and concertedmovement with said first named member and defining therewith saidchamber, said first named and other members being concertedly movable inresponse to the applied force to establish pressure fluid flow throughsaid flow passage when the fluid pressure in said chamber exceeds thepredetermined value, and resilient means effecting the automaticmovement of said other member relative to said first named member toestablish pressure fluid flow through said flow passage when the fluidpressure in said chamber is less than the predetermined value.

5. The control valve according to claim 4, comprising abutment meansengaged between said first named and other members to provide for theconcerted movement thereof when the fluid pressure in said chamber.exceeds the predetermined value.

6. The control valve according to claim 1, comprising valve meanscontrolling said flowpassage, said application means being movable inresponse to theapplied force to engage and move said valve means towardan openposition in saidflow passage to establish the pressure fluidflow'theret'hrough, said valve means also being engaged and actuated bysaid resiliently urged means in response to the automatic movementthereof.

7. The control valve according to claim 4, comprisin valve meanscontrolling said flow passage, extension means on said first namedmember for operative engagement with said valve means, said first namedmember being movable in response to the applied force to engage saidextenison-means with said valve means and mov said valve means toward anopen position in said flow passage establishing the pressure fluid flowtherethrough.

8. The control valve according to claim 7, wherein said other memberincludes other extension means movable in said first namedextension-means for operative engagement with said valve means, saidother extension means being moved into engagement with said valve meansto eflect actuation thereof upon the automatic movement of said othermember.

9. The control valve according to claim 4, comprising valve meanscontrolling said. flow passage, said other member including extensionmeans movable in said first named member and extending into said flowpassage for operative engagement with said valve means, said first namedand other members being concertedly movable in response to the appliedforce to engage said extension means with said valve means and move saidvalve means toward an open position in said flow passage establishingthe pressure fluid flow therethrough, and said extension means alsobeing movable into engagement with said valve means to effect actuationthereof upon the automatic movement of said other member.

10. A control valve comprising a housing having inlet, outlet andcontrol ports therein, a pair of application means concertedly andrelatively movable in said housing, valve means controlling pressurefluid communication between said inlet a-nd outlet ports, an expansiblefluid pressure chamber defined'bctween said application means, meanswithin said housing including one of said application means definingpassage means connecting said chamber in pressure fluid communicationwith said control port,

, resilient means urging the other of said application means towardoperative engagement with said valve means and opposing fluid pressureexpansion of said chamber, said other application means being movablerelative to said one application means in response to the force of saidresilient means to engage and move said valve means toward a positionestablishing pressure fluid communication between said inlet and outletports when the fluid pressure at said control port is less than apredetermined value, said other application means also being movablerelative to said one application means and against said resilient meanstoward a retracted position when the fluid pressure in said chamberexceeds the predetermined value, and said one and other applicationmeans being concertedly movable when said one application means is inthe retracted position thereof in response to an applied force to engageone of said one and other application means with said valve means andeffect actuation thereof.

11. The control valve according to claim 10, comprising a reaction areaon said other application means responsive to the established fluidpressure at said outlet port to oppose the resilient means movement ofsaid other application means.

12. The control valve according to claim 11, comprising another reactionarea on said other application means responsive to the fluid pressure atsaid control port and additive to said first named reaction area, theforce of the established fluid pressure at said outlet port acting onsaid first named reaction area and compensating for the reduction of theadditive forceof the fluid pressure at said control port acting on saidother area when the fluid pressure at said control port is less than thepredetermined value.

13. The control valve according to claim 10, comprising means on saidone application means for operative engagement with said valve means,the concerted applied force movement of said one and other applicationmeans serving to engage said last named means with said valve means andeffect actuation thereof.

14. The control valve according to claim 13, wherein said otherapplication means includes other means movable through said last namedmeans for operative engagement with said valve means, said other meansbeing moved into engagement with said valve means to effect actuationthereof upon the resilient means movement of said other applicationmeans.

15. The control valve according to claim 10, wherein said otherapplication means includes extension means movable in said oneapplication means and having a free end portion for operative engagementwith said valve means, said end portion being moved into engagement withsaid valve means to effect actuation thereof upon the concerted appliedforce movement of said one and other application means and upon theresilient means movement of said other application means.

16. The control valve according to claim 10, comprising an inlet chamberin said housing connected with said inlet port, said one and otherapplication means defining with said housing an outlet chamber connectedwith said outlet :port, a connecting passage in said housing betweensaid inlet and outlet chambers, a valve seat on said housing incircumscribing relation with said connecting passage, said valve meansbeing normally urged into engagement with said valve seat to close saidconnecting passage and interrupt pressure fluid communication betweensaid inlet and outlet ports, the concerted applied force movement ofsaid one and other application means and the resilient means movement ofsaid other application means serving to actuate said valve means towarda position disengaged from said valve seat to open said connectingpassage and establish the pressure fluid communication between saidinlet and outlet ports, respectively.

17, The control valve according to claim 10, comprising a bore andcounterbore in said housing having wall means therebetween, said inletand outlet ports respectively intersecting with said bore andcounterbore, a connecting passage extending through said wall meansbetween said bore and counterbore, a valve seat on said wall means incircumscribing relation with said connecting passage, said valve meansbeing normally urged into engagement with said valve seat closing saidconnecting passage and being actuated to a position disengaged from saidvalve seat and opening said connecting passage in response to theconcerted applied force movement of said one and other application meansand in response to the resilient means movement of said otherapplication means, said one application means being movable in saidcounterbore between the end thereof opposite said wall means and saidoutlet port, another bore in said one application means, spaced abutmentmeans in said other bore, said other application means being movable insaid other bore between said abutment means, said resilient meansincluding spring means having opposed ends, one of said spring meansopposed ends being biased into engagement with said other applicationmeans urging said other application means toward one of said abutmentmeans, retainer means in said bore for engagement with said otherabutment means, the other of said spring means opposed ends being biasedinto engagement with said retainer means urging said retainer means intodisplacement preventing engagement with said other abutment means, saidchamber being defined in said bore between said one and otherapplication means, and said passage means including peripheral groovemeans in said one application means connected in open pressure fluidcommunication with said control port, and another connecting passage insaid one application means having one end intersecting with said groovemeans and the other end thereof intersecting with said other bore.

18. The control valve according to claim 10, comprising a stepped borein said one application means having a shoulder therebetween, abutmentmeans in the larger of said stepped :bores and spaced from saidshoulder, said other application means including a stepped member, thelarger portion of said stepped member being movable in said largerstepped bore between said shoulder and abutment means and the smallerportion of said stepped member being movable through the smaller of saidstepped bores for engagement with said valve means, said resilient meansincluding spring means having opposed ends, one of said opposed endsbeing biased into engagement with said stepped member larger portionurging said stepped member larger portion toward said shoulder, andretainer means in said larger stepped bore and normally urged intodisplacement preventing engagement with said abutment means, said otheropposed end of said spring means being biased into engagement with saidretainer means, and said chamber being defined in said larger steppedbore between said shoulder and said stepped member.

19. The control valve according to claim 10, comprising a bore in saidone application means, a pair of spaced abutment means in said bore,said other application means being movable in said bore between saidabutment means, said chamber being defined in said bore between said oneand other application means, retainer means for displacement preventingengagement with one of said abutment means, said resilient meansincluding a spring biased between said retainer means and said otherapplication means, the compressive force of said spring urging saidother application means toward the other of said abutment means andurging said retainer means into displacement preventing engagement withsaid one abutment means, and said chamber being defined in said borebetween said one and other application means.

20. The control valve according to claim 10, comprising a fluid pressuresource, and selecltively operable means for selectively connecting saidcontrol port in pressure fluid communication with said source and theatmosphere, said other application means being urged toward itsretracted position for concerted applied force movement with said oneapplication means in response to the fluid pressure at said control portin excess of the predetermined value when said selectively operablemeans connects said control port with said source, and said otherapplication means being relatively movable in response to the force ofsaid resilient means when said selectively operable means connects saidcontrol port to the atmosphere.

21. A control valve comprising a housing having inlet and outlet portstherein, valve means controlling pressure fluid communication betweensaid ports, a valve control member movable in said housing for operativeengagement with said valve means, said valve control member beingmovable in response to an applied force to engage and move said valvemeans toward a position establishing pressure fluid communicationbetween said ports, resiliently urged means movable in said valvecontrol member for operative engagement with said valve means, saidresiliently urged means being movable in concert with and relative tosaid valve control member, and an expansible fluid pressure chamberdefined between said valve control member and said resiliently urgedmeans, said resil- 1 1 iently urged means being retractively movablerelative to said valve control member toward a retracted position forconcerted applied force movement therewith when the fluid pressure insaid chamber exceeds the predetermined value and said resiliently urgedmeans being protra ctively movable relative to said valve control membertoward a protracted position to engage and move said valve means towardits position establishing the pressure fluid communication between saidports.

No references cited.

EUGENE G. BOTZ, Primary Examiner.

1. A CONTROL VALVE COMPRISING A HOUSING, APPLICATION MEANS MOVABLE INSAID HOUSING AND DEFINING WITH SAID HOUSING A PRESSURE FLUID FLOWPASSAGE THERETHROUGH, SAID APPLICATION MEANS BEING MOVABLE IN RESPONSETO AN APPLIED FORCE TOWARD A POSITION IN SAID FLOW PASSAGE ESTABLISHINGPRESSURE FLUID FLOW THERETHROUGH, SAID APPLICATION MEANS INCLUDING ANEXPANSIBLE FLUID PRESSURE CHAMBER, AND RESILIENTLY URGED MEANS OPPOSINGFLUID PRESSURE EXPANSION OF SAID CHAMBER, SAID RESILIENTLY URGED MEANSBEING AUTOMATICALLY MOVABLE TOWARD A POSITION IN SAID FLOW PASSAGE TOESTABLISH PRESSURE FLUID FLOW THERETHROUGH IN RESPONSE TO FLUIE PRESSUREIN SAID CHAMBER LESS THAN A PREDETERINED VALUE.